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Each year, extreme sports is the direct cause of thousands of head and neck injuries among non-professionals, according to a new study that underscores the importance of thinking twice before mimicking TV stunts.

Dr. Vani Sabesa, a researcher at Western Michigan University School of Medicine and co-author of the new study, told HealthDay that conversations about skateboarding, snowboarding, and mountain biking typically lose sight of the serious risks associated with the sports. "We know that youth tends to push the envelope and take things to the next level," she said. "So the tricks involved in these increasingly popular sports are becoming more and more advanced every year.

“And that means more and more accident risk," she added.

To investigate, Sabesa and her colleagues looked at data collected by the National Electronic Injury Surveillance System between 2000 and 2011. Within this set, they looked for accidents related to surfing, mountain biking, motocross, skateboarding, snowmobiling, snowboarding, and skiing. They found that more than 4 million cases fit the description.

The results, which will be presented at the annual meeting of the American Academy of Orthopaedic Surgeons (AAOS) in New Orleans, show that one out of every 10 injuries linked to these seven sports are to the head or neck. About 2.5 percent of these were classified as severe, which means that they involved fractures. Skull injuries were by far the most common.

The sport that produced the most injuries was skateboarding, with more than 129,000 head and neck injuries recorded over the 11-year period. At a close second was snowboarding, which was associated with 97,000 cases. Skiing and motocross were third and fourth, with 83,000 and 78,000 cases, respectively.

What’s worse, there’s good reason to believe that these figures will continue to rise, as extreme sports appear to be gaining more popularity each year. The number of Americans who skateboard, for example, has grown by nearly 50 percent since 1999. Today, more than 14 million skate on a regular basis.

“The research provides a baseline to further study head and neck injuries among extreme sport participants,” Sabesa explained. “There’s an understanding that these sports are growing in participation, and that they can result in significant injuries.”

Sabesa added that improving safety is possible, but will require efforts from parents as well as organizers. “In general we need to make sure protective equipment is available — such as helmets and wrist guards — and encouraged. And we need to make sure we provide medical care and team doctors on site, and that kids know that it's possible to get a concussion when doing these sports and are encouraged to seek medical help when there's any concern,” she told reporters.